Typical of Slavic languages, Czech marks its verbs for one of two grammatical aspects: perfective and imperfective. Most verbs are part of inflected aspect pairs—for example, koupit (perfective) and kupovat (imperfective). Although the verbs' meaning is similar, in perfective verbs the action is completed and in imperfective verbs it is ongoing. This is distinct from past and present tense, and any Czech verb of either aspect can be conjugated into any of its three tenses. Aspect describes the state of the action at the time specified by the tense.
What describes the state of the action of the verb at the time specified by its tense?
Aspect

As anticipated by Nimitz, the Japanese fleet arrived off Midway on 4 June and was spotted by PBY patrol aircraft. Nagumo executed a first strike against Midway, while Fletcher launched his aircraft, bound for Nagumo's carriers. At 09:20 the first U.S. carrier aircraft arrived, TBD Devastator torpedo bombers from Hornet, but their attacks were poorly coordinated and ineffectual; thanks in part to faulty aerial torpedoes, they failed to score a single hit and all 15 were wiped out by defending Zero fighters. At 09:35, 15 additional TBDs from Enterprise attacked in which 14 were lost, again with no hits. Thus far, Fletcher's attacks had been disorganized and seemingly ineffectual, but they succeeded in drawing Nagumo's defensive fighters down to sea level where they expended much of their fuel and ammunition repulsing the two waves of torpedo bombers. As a result, when U.S. dive bombers arrived at high altitude, the Zeros were poorly positioned to defend. To make matters worse, Nagumo's four carriers had drifted out of formation in their efforts to avoid torpedoes, reducing the concentration of their anti-aircraft fire. Nagumo's indecision had also created confusion aboard his carriers. Alerted to the need of a second strike on Midway, but also wary of the need to deal with the American carriers that he now knew were in the vicinity, Nagumo twice changed the arming orders for his aircraft. As a result, the American dive bombers found the Japanese carriers with their decks cluttered with munitions as the crews worked hastily to properly re-arm their air groups.
How many TBD Devastator torpedo bombers were lauched from the Hornet?
15

Pubertal development also affects circulatory and respiratory systems as an adolescents' heart and lungs increase in both size and capacity. These changes lead to increased strength and tolerance for exercise. Sex differences are apparent as males tend to develop "larger hearts and lungs, higher systolic blood pressure, a lower resting heart rate, a greater capacity for carrying oxygen to the blood, a greater power for neutralizing the chemical products of muscular exercise, higher blood hemoglobin and more red blood cells".
Which body system are a person's lungs a major proponent of?

respiratory